Bad for your health?

15th of June 2010

Today, one in five workers in Europe is employed on shift work involving night work and the cleaning sector is significantly affected. Research has shown, however, that regular night work can have detrimental effects for the employee in terms of health and wellbeing. ECJ takes a closer look at the issue.

Across Europe, cleaners are working in buildings at different times of the day and night - the nature of the job and our increasingly 24-hour society mean that unsociable working hours are commonplace. Research has shown, however, that regular night work can have detrimental effects on the employee in terms of health and wellbeing - indeed a European directive imposes various restrictions on how it is carried out.

Simply ascertaining what a night worker is, however, is not as straightforward as it may seem. The definition of 'night worker' in article 2(4) of the Directive 93/104/EC by the European Commission is complex. It defines a ‘night worker’ as ‘on the one hand, any worker, who, during night time, works at least three hours of his daily working time as a normal course’. 'Night time’ is defined in Article 2(3) as ‘any period of not less than seven hours, as defined by national law, and which must include in any case the period between midnight and 5 am’.

Moreover, collective bargaining plays a role in defining night workers. For example, 'night worker' also means: 'any worker who is likely during night time to work a certain proportion of his annual working time, as defined, at the choice of the member state concerned: by national legislation, following consultation with the two sides of industry, or by collective agreements or agreements concluded between the two sides of industry at national or regional levels.'

With the definitions out of the way, what the directive does is specify maximum night work by prohibiting more than eight hours’ night working in a 24-hour period on average. As night shifts often involve particular hazards or physical or mental strain it stipulates that night workers must have a level of safety and health protection adapted to the nature of their work. They are entitled to a free health assessment before being assigned to night work and thereafter at regular intervals. If they are deemed to be unsuited to night work, they must be transferred to day work where possible.

Consequences on the body

So apart from the obvious negative effects of night working on family and social life, what are the possible consequences of night working on the body? Studies suggest that when you are awake at night and asleep during the day, your body does not receive powerful biological cues from the amount of light in the environment. These cues are necessary to regulate the natural circadian rhythm - the body's internal clock - that controls your sleep/wake cycle.

This causes difficulty in falling asleep and getting enough deep sleep. Another problem comes in switching from a night schedule to a day schedule on days off, or during changes in the work shift. This switching causes the same effects as jet lag. The body needs one hour per day to adjust to changes in sleep.

The effects of disturbing our natural body clock, however, can have much more serious consequences for the body. Our complex timing system manages a variety of physiological events, including blood pressure, secretion of stomach acids, and even the degree to which we experience pain. So in the short term, working a night shift may make you feel fatigued and less alert - you may find it difficult to make decisions and communicate thoughts, and you are more likely to have an accident.

Long term consequences, however, include gastrointestinal problems (chronic heartburn and indigestion), weight gain, high blood pressure and a greater risk of cardiovascular disease and heart attack. Emotional problems also occur more frequently. Women working night shifts, for example, have increased menstrual difficulties and problems with infertility.

Counter the effects

Fortunately, there are some proven ways to counter the effects of working night shifts.

•If you must work at nights, change your daily schedule as little as possible. For example if you work for several days and then take a few days off, try to keep your sleeping hours the same even when you are not working.

•If you must change your shift, try to move it forward. Changing the start of your working day from 7am to 3pm is easier, for example, than from 3pm to 7am.

•While working at night, try to be in as much bright light as possible - this will help your body to regulate its sleep/wake cycle.

•To sleep better during the day, avoid sunlight for at least an hour before you go to bed.

•Keep your bedroom as cool and as dark as possible and if necessary use earplugs and a sleep mask to minimise distractions.

•While working at night, adjust your lifestyle so that your schedule runs work-sleep-leisure, rather than the work-leisure-sleep schedule of day workers.

•Avoid cigarettes and excessive caffeine, and resist using sleeping pills or alcohol to induce drowsiness or stimulant drugs to stay awake.

•Try to get plenty of exercise during breaks in your night shift. If that is not possible, take some exercise before you start work. But avoid any strenuous exercise just before you need to sleep.

In various studies carried out among night workers, it is interesting to note that some did list a number of positive effects of their nocturnal hours. Many participants said they got more time off when they worked longer shifts that included unsocial hours and some even benefit from extra leave. Another positive aspect is pay, with many night workers reporting extra pay for working unsocial hours. And while working at night may cause problems for some families, for others it brings the ability to spend more time with their family and a reduced need for childcare.

So while for many cleaners night work may be unavoidable at some times, it appears that the flexibility of not working a standard 9am to 5pm day actually suits their lifestyle and family commitments. And with some planning and effort, the more unpleasant effects can be minimised.